JP5251254B2 - Target adsorption device and recording device - Google Patents

Description

  The present invention relates to a recording apparatus such as, for example, an ink jet printer, and a target suction apparatus provided in the recording apparatus.

  Conventionally, as a recording apparatus equipped with a target suction device, an image forming apparatus that transfers and fixes a toner image onto a conveyed sheet-like target, or a character or image by ejecting ink from a recording head to a conveyed target Inkjet recording apparatuses (hereinafter referred to as “printers”) are known (see, for example, Patent Document 1 and Patent Document 2). A target suction device provided in such an image forming apparatus or printer has a suction duct that generates a negative pressure based on the drive of a suction fan (suction means), and an endless drive that is driven around with the suction duct installed inside. A plurality of suction holes are formed in the entire area of the conveyor belt in the width direction orthogonal to the target conveyance direction. Then, by sucking the inside of the suction hole of the transport belt that is supporting the target through the suction duct based on the drive of the suction fan, the target is transported to the downstream side while being adsorbed on the transport belt that moves around. It is like that.

  However, in the image forming apparatus described in Patent Document 1, the suction duct is configured by a single negative pressure chamber. That is, when sucking the inside of each suction hole of the transport belt through the suction duct and trying to suck the target, all the suction holes corresponding to the suction duct in the transport belt are blocked from communication with the atmosphere. As long as the suction fan is driven, the suction duct is configured such that a negative pressure (suction pressure) that can attract the target cannot be obtained even if the suction fan is driven. For this reason, in the image forming apparatus disclosed in Patent Document 1, the front end of the target in the transport direction reaches the downstream end of the suction duct in the transport direction with respect to the target transported while being supported by the transport belt. In the previous stage, there was a possibility that the suction force could not be applied reliably unless the suction fan exhibited a strong suction force.

On the other hand, in the printer described in Patent Document 2, a plurality of suction ducts are arranged in parallel with each suction duct having a suction fan along the target transport direction, and all the suction ducts are disposed inside. The conveyor belt with suction holes is provided so as to circulate in a state where it is installed in the cylinder. For each of the suction ducts, a group of suction holes in the transport belt communicating with the suction duct is covered with the target when the downstream end of the suction duct passes through the front end in the transport direction of the target. It has become so. That is, even with respect to a target that is transported in a state supported by the transport belt, the front end of the target in the transport direction reaches the downstream end in the transport direction of the suction duct disposed on the most downstream side. A desired negative pressure (suction pressure) is generated in the suction duct arranged on the upstream side in the transport direction so that the suction force can be reliably applied.
JP 2006-168890 A JP 2005-169990 A

  Incidentally, the printer described in Patent Document 2 has a configuration in which a suction fan is installed for each of a plurality of suction ducts arranged in parallel along the transport direction. For this reason, there has been a problem that the increase in the number of suction fans is accompanied by an increase in the size of the entire apparatus and an increase in the manufacturing cost of the entire apparatus.

  The present invention has been made in view of such circumstances, and an object of the present invention is to reliably apply a suction force to a target to be transported during transport while reducing the number of suction means installed. An object of the present invention is to provide a target adsorption device and a recording device.

In order to achieve the above object, the target adsorption device of the present invention has a support surface capable of supporting a target conveyed from the upstream side to the downstream side, and a plurality of suction holes are formed on the support surface. A plurality of negative pressure chambers individually communicating with each of the suction hole groups when the suction holes are divided into a plurality of suction hole groups with respect to the plurality of suction holes of the support member; Suction means capable of generating a negative pressure in each of the negative pressure chambers through communication members individually extending from the negative pressure chambers, and the communication members are formed to have a right cylindrical shape. And when the suction holes in the suction hole group communicating with some of the plurality of negative pressure chambers are closed, the target is removed via the suction hole group communicating with the negative pressure chamber. To apply the required suction force necessary for adsorption, the required suction force is applied. In the communicating member that accompanies the driving of the suction means, the required static pressure necessary for generating the suction means and the required air volume corresponding to the required static pressure defined by the static pressure-air volume curve of the suction means can be generated. The total pressure loss of the fluid is set , the area of the target is S, the opening density of the opening for exerting a suction force on the target is Y, the length of the communicating member is L, and the diameter of the communicating member is D, the number of the negative pressure chambers connected to the suction means is A, the friction coefficient in the communication member is k, the pressure loss coefficient in the connection portion of the communication member to the negative pressure chamber is ζ _in , and the communication member The conditional expression to be satisfied when the pressure loss coefficient at the connection to the suction means is ζ _out , the required suction force applied to the target is X, and the air volume corresponding to the minimum value X ₁ of the required suction force is Q ₁ is: ( 00 is a × X) / (S × Y ) ≦ 0.974 × {1 + k × (L / D) + ζ in + ζ out} × _{[Q 1 / {(A-1} ) × D 2} ] ^2.

  Usually, in the stage before the tip of the target in the transport direction reaches the downstream end of the support surface of the support member, it is arranged downstream of the plurality of suction hole groups formed on the support surface. The downstream suction hole group whose target is not yet covered with the suction opening is open to the atmosphere. Then, among the plurality of negative pressure chambers corresponding to the plurality of suction hole groups, the downstream negative pressure chamber corresponding to the downstream suction hole group is brought into the atmosphere via the suction holes of the suction hole group in the open state. Communicate. Therefore, as the suction means is driven, fluid (atmosphere) flows into the suction means via the negative pressure chamber corresponding to the downstream suction hole group and the communication member connected to the negative pressure chamber. No negative pressure is generated in the downstream negative pressure chamber corresponding to the downstream suction hole group. In this case, the upstream negative pressure chamber corresponding to the upstream suction hole group in which the suction opening is already covered by the target is also connected to the suction means and the communication member connected to the negative pressure chamber. Since fluid (atmosphere) flows in, no negative pressure is generated in the upstream negative pressure chamber corresponding to the upstream suction hole group. As a result, when the target passes over the upstream suction hole group, all the plurality of negative pressure chambers cannot be set to negative pressure, and suction force cannot be reliably applied to the target. There was a fear.

  In this regard, according to the above configuration, the negative pressure chamber corresponding to the downstream suction hole group is against the atmosphere before the tip end in the target transport direction reaches the downstream end on the support surface of the support member. Even in the open state, the pressure loss of the fluid (atmosphere) flowing into the communicating member connected to the downstream negative pressure chamber due to the driving of the suction means is caused in the upstream suction hole group. The shape of the communicating member is designed so as to have an appropriate value for generating a desired negative pressure in the corresponding upstream negative pressure chamber. Therefore, a plurality of negative pressure chambers individually corresponding to the plurality of suction hole groups are configured to be sucked by a common suction means, so that the number of suction means installed is reduced and the target to be transported is being transported. It is possible to reliably apply a suction force in step (b).

In addition, the communication member calculates the total pressure loss by summing up the pressure loss reflecting the configuration of the shaft portion having a straight cylindrical shape, the connection portion to the negative pressure chamber, and the connection portion to the suction means, and the calculation result and By considering the static pressure-air volume curve of the suction means, a conditional expression relating to the structure of the communicating member necessary for applying a desired suction force to the target is calculated. Therefore, by configuring the communication member so as to satisfy this conditional expression, a desired suction force can be more reliably applied to the target. The friction coefficient k in the communication member can be assumed to be 0.02 when the inner wall of the communication member is smooth and has little friction. Further, the pressure loss coefficient ζ _in of the connecting portion with respect to the negative pressure chamber of the communication member can be assumed to be 0.5 when the opening of the connecting portion is a corner end.

The target suction device of the present invention further includes a transport body that moves to transport the target from the upstream side toward the downstream side in a state where the target is supported, and the transport body moves the transport body. In the middle, the support member has a plurality of communication portions that can communicate with the suction holes, and the support member can support the target through the transport body by the support surface. It is the said communication part of a conveyance body.

  According to the above configuration, since the transport body that transports the target on the support surface of the support member is provided, the shape of the target is not limited to a long one, and for example, a sheet-like target is applied. Is possible. In addition, since the transport body has a communication portion that communicates with the suction hole of the support member, the target placed on the upper surface of the transport body when the suction force from the suction hole reaches the target through the communication portion. Can be reliably adsorbed to the carrier. In the above configuration, a transport body that transports the target on the support surface of the support member is provided. However, by applying the opening density of the communication portion of the transport body to the conditional expression, a desired suction with respect to the target is achieved. It is possible to determine the structure of the communication member that is necessary for applying the force.

  In addition, the recording apparatus of the present invention includes a recording unit that performs a recording process on a target supported on the support surface of the support member, and a target suction device having the above-described configuration. According to the said structure, the effect similar to the said target adsorption | suction apparatus is acquired.

  Hereinafter, an embodiment in which the recording apparatus of the present invention is embodied in an ink jet printer will be described with reference to the drawings. In the following description, when referring to “vertical direction”, “front / rear direction”, and “left / right direction”, the direction indicated by the arrow in the figure is used as a reference.

  As shown in FIG. 1, an ink jet printer (hereinafter referred to as “printer”) 11 as a recording apparatus includes a transport mechanism 13 as a target suction device that transports paper 12 as a target in a sucked state. . The transport mechanism 13 includes a first transport unit 15 that transports the paper 12 fed from the paper feed tray 14 positioned on the upstream side (left side) in the transport direction to the downstream side (right side), and the first transport unit 15 The transported paper 12 is further composed of a second transport unit 17 that transports the transported paper 12 further downstream and discharges it to a paper discharge tray 16.

  Each of the conveying units 15 and 17 is driven to rotate by a driving force of a motor (not shown) and the first driving pulley 18 and the second driving pulley 19 whose axes are parallel to each other, and the axis of each driving pulley 18 and 19 Each of the first driven pulley 20 and the second driven pulley 21 is rotatable around a parallel axis. Further, a first conveying belt 22 as an endless conveying member is stretched between the first driving pulley 18 and the first driven pulley 20, and the second driving pulley 19 and the second driven pulley 21. A second conveyor belt 23 as an endless conveyor is stretched between them. Then, the conveying belts 22 and 23 rotate in accordance with the rotational driving of the corresponding drive pulleys 18 and 19 so that the paper 12 fed from the paper feeding tray 14 is placed on the first conveying belt 22. In this state, the paper is transported from the first transport unit 15 to the second transport unit 17 and further transported to the paper discharge tray 16 while being placed on the second transport belt 23.

  Further, as shown in FIG. 1, a recording head 24 as a recording unit is disposed at a position above the first conveying belt 22 in the first conveying unit 15. In addition, a plurality of nozzle rows (not shown) along the width direction of the paper 12 (the direction orthogonal to the paper surface in FIG. 1) are spaced apart from the nozzle forming surface 24a, which is the lower surface of the recording head 24, in the transport direction. Are lined up. Then, the recording head 24 performs printing (recording processing) on the paper 12 by ejecting ink so as to cover the entire width direction as the paper 12 passes below the recording head 24. It has become.

  Further, drying of the paper 12 transferred from the first conveying belt 22 to the second conveying belt 23 is promoted to a position upstream of the second conveying unit 17 and above the second conveying belt 23. For this purpose, a heatable heater 25 is provided.

  Moreover, in each conveyance part 15 and 17, between the 1st drive pulley 18 and the 1st driven pulley 20, and between the 2nd drive pulley 19 and the 2nd driven pulley 21, the support by which the upper surface was formed in planar shape A first support base 26 and a second support base 27 are disposed as members. And when each conveyance belt 22 and 23 carries out the revolving motion, the back surface of the belt part which mounts the paper 12 in each conveyance belt 22 and 23, and conveys it downstream (from the left side to the right side), respectively corresponds support. The bases 26 and 27 are in sliding contact with the upper surfaces.

  Moreover, in each conveyance part 15 and 17, each conveyance belt 22 and 23 and each support stand 26 and 27 are each formed with the some hole. In addition, since the conveyance belts 22 and 23 and the support bases 26 and 27 in each conveyance part 15 and 17 have the respectively same structure, only the conveyance belt 23 and the 2nd support base 27 in the 2nd conveyance part 17 are demonstrated. The description of the other transport unit 15 is omitted.

  As shown in FIG. 2, the second transport belt 23 is configured such that the surface 23 a functions as a placement surface when transporting the paper 12. A large number of communication holes 28 as communication portions are formed in the second transport belt 23 so as to penetrate the front surface 23 a serving as the mounting surface and the back surface that is in sliding contact with the second support 27. The communication holes 28 are regularly arranged so as to form a plurality of rows of communication holes 29 along the front-rear direction at predetermined intervals in the left-right direction.

  Further, the second support 27 is configured such that its upper surface 27 a functions as a support surface capable of supporting the paper 12 through the second transport belt 23. A suction hole that penetrates the second support base 27 in the vertical direction (thickness direction of the second support base 27) is formed in the second support base 27 so that a suction opening opens on the upper surface 27a serving as the support surface. Many 30 are formed. Each suction hole 30 is formed at a position corresponding to each communication hole 28 of the second conveying belt 23 in the front-rear direction and at a position wider than each communication hole 28 in the left-right direction. . These suction holes 30 are regularly arranged so as to form a plurality of suction hole arrays 31 along the front-rear direction at predetermined intervals in the left-right direction. The suction opening (opening on the upper surface 27a side) in each suction hole 30 is formed in a long groove shape along the left-right direction.

  As shown in FIGS. 2 to 4, a plurality of rows (12 rows in the present embodiment) of suction hole rows 31 are arranged on the lower side of the second support base 27 in the conveyance direction (left-right direction) of the paper 12. When divided into a plurality of (four in this embodiment) suction hole groups 32 each having three rows (in this embodiment, three rows), the openings on the lower surface side of the suction holes 30 in each suction hole group 32 are covered. A cover member 33 having a box shape is individually provided for each suction hole group 32. In addition, a circular communication hole 34 having a diameter D (m) in a plan view is formed in the bottom surface portion of each cover member 33 in the vertical direction, and the length L (m) with the communication hole 34 side as a base end. A straight cylindrical communication member 35 extends vertically downward. That is, the communication member 35 functions as a linear portion in which the shaft portion 35 a extends linearly along the vertical direction, and the base end portion 35 b functions as a connection portion that communicates with the cover member 33 through the communication hole 34. It has become. The opening (communication hole 34) on the cover member 33 side of the communication member 35 is formed to have a corner end shape.

  In addition, below each communication member 35, an induction blower 37 is provided as a box-like suction unit that accommodates the suction fan 36 therein. Further, on the upper surface of the induction blower 37, communication holes 38 are formed at positions corresponding to the communication holes 34 of the cover members 33 in the vertical direction. And each communication member 35 functions as a connection part which the front-end | tip part 35c communicates with the induction blower 37 side via the corresponding communication hole 38, respectively.

  When the suction fan 36 is rotated by driving the induction blower 37, the inside of the cover member 33 is sucked through the communication member 35, thereby generating a negative pressure in the cover member 33. That is, the internal space of the cover member 33 having a box shape is configured to function as a negative pressure chamber 33 a in which a negative pressure is generated as the induction blower 37 is driven. Further, when a negative pressure is generated in the negative pressure chamber 33a in the cover member 33, the negative pressure similarly acts in each suction hole 30 communicating with the negative pressure chamber 33a. The sheet 12 is sucked to the 27 side. Then, the suction force from each suction hole 30 reaches the paper 12 placed on the second transport belt 23 through the communication hole 28, so that the paper 12 is attracted to the second transport belt 23. Yes.

  Here, the structure of the communication member 35 (that is, the circular diameter D (m) in plan view and the length L (m) in the longitudinal direction (vertical direction)) is such that the suction openings of some of the suction hole groups 32 are open. Even in such a case, it is designed so that a desired suction force acts on the paper 12. Specifically, an estimated value of the total pressure loss of air as a fluid flowing in the communication member 35 with the driving of the induction blower 37 is calculated, and a conditional expression regarding the structure of the communication member 35 is calculated based on this estimated value. It is set. This conditional expression will be described below.

  First, the speed pressure Pv is calculated by the equations 1 and 2. The velocity pressure Pv is a dynamic pressure (Pa) in the flow direction that is necessary for causing stationary air to flow at a predetermined velocity, and is represented by Equation 1.

[Formula 1]
Pv = (V / 4.04) ² × 9.81
[V: Flow velocity of air flowing in communication member 35 (m / s)]
Note that the flow velocity V in Equation 1 is the air volume per unit area of the air flowing in the communication member 35 as shown in Equation 2.

[Formula 2]
V = air volume / cross-sectional area = (Q / n) / {π × (D / 2) ² } = 4Q / nπD ²
[Q: Flow rate of air flowing in the communication member 35 (m ³ ), n: Number of communication members 35 communicating with the suction hole group 32 in the open state]
Substituting Equation 2 into Equation 1 yields Equation 3.

[Formula 3]
Pv = 0974 × (Q / nD ² ) ²
Here, the static pressure P _s required to cause the predetermined air volume Q to flow in the communication member 35 is the total pressure loss P _total and velocity pressure P of the air flowing in the communication member 35 as shown in Equation 4. _v is the sum.

[Formula 4]
P _s = P _v + P _total
The total pressure loss _{P total,} as shown in Equation 5, the pressure loss _{P L} and base end portion 35b of the communicating member 35 (covering member 33 side of the connection portion of the shaft portion 35a of the communicating member 35 (linear portions) and the pressure loss _{P in} the), which is the sum of the pressure loss _{P out} of the distal end portion 35c of the communicating member 35 (connecting portions of the attraction blower 37 side).

[Formula 5]
P _total = P _L + P _in + P _out
The pressure loss P _L is a pressure loss that air undergoes in the process of flowing through the shaft portion 35a of the communication member 35, and is expressed by Equation 6.

[Formula 6]
P _L = k × (L / D) × P _v
[K: Coefficient of friction with respect to air on inner wall of communication member 35 (In this embodiment, since the inner wall of communication member 35 is a smooth surface with less friction against air, it can be assumed that k = 0.02)]
Pressure loss P _in is the pressure loss which receives in the process of flowing into the communication member 35 air through an opening of the covering member 33 side is expressed by Equation 7.

[Formula 7]
P _in = ζ _in × P _v
[Ζ _in : Pressure loss coefficient of the inlet (communication hole 34) of the communication member 35 (in this embodiment, since the communication hole 34 is formed to have a square end shape, it can be assumed that ζ _in = 0.5. )]
The pressure loss _Pout is a pressure loss that air undergoes in the process of flowing out of the communication member 35 through the opening on the side of the induction fan 37, and is expressed by Expression 8.

[Formula 8]
P _out = ζ _out × P _v
[Ζ _out : Pressure loss coefficient at the outlet of the communication member 35 (in this embodiment, it can be assumed that ζ _out = 0.5)]
Substituting Equations 6 to 8 into Equation 5 yields Equation 9.

[Formula 9]
P _total = {k × (L / D) + ζ _in + ζ _out } × P _v
Substituting Equation 9 into Equation 4 yields Equation 10.

[Formula 10]
P _s = {1 + k × (L / D) + ζ _in + ζ _out } × P _v
Substituting Equation 3 into Equation 10 yields Equation 11.

[Formula 11]
P _s = 0.974 × {1 + k × (L / D) + ζ _in + ζ _out } × (Q / nD ² ) ²
Note that the suction force X (N) applied to the paper 12 on the second transport belt 23 is expressed by Expression 12.

[Formula 12]
X = {S × (Y / 100)} × P _s
[S: area of sheet 12 (m ² ), Y: opening density for applying suction force to sheet 12 (in this embodiment, unit area on second transport belt 23 (dotted line in FIG. 5) The area density of the communication holes 28 per area (area A) surrounded by (%))]
If this is arranged, it will become like Formula 13.

[Formula 13]
P _s = (100 × X) / (S × Y)
Substituting Equation 13 into Equation 11 yields Equation 14.

[Formula 14]
(100 × X) / (S × Y) = 0.974 × {1 + k × (L / D) + ζ _in + ζ _out } × (Q / nD ² ) ²
In addition, the graph shown in FIG. 6 is a static pressure-air volume curve in which the correlation between the static pressure and the air volume in the induction blower 37 of the present embodiment is shown based on actual measurement values, and the static pressure increases as the air volume decreases. Is shown. Here, the required necessary for the paper 12 to impart the required suction force X required for adsorbing the sheet 12 to the second conveyor belt 23, the action of the minimum value X ₁ of said predetermined main attraction X _{P 1} the minimum value of static pressure _{P s,} and the flow rate corresponding to the minimum value _{P 1} of said predetermined Yosei圧_{P s} and _{Q 1.} Then, as shown in FIG. 6, in order to obtain the required static pressure P _s equal to or higher than P ₁ (that is, to apply the required suction force X equal to or higher than X ₁ to the paper 12), the communication member 35 It is necessary and sufficient condition that the required air volume Q of the air flowing inside is Q ₁ or less.

[Formula 15]
Q ≦ Q ₁
Then, when the formulas 14 and 15 are arranged, the formula 16 is obtained.

(100 × X) / (S × Y) ≦ 0.974 × {1 + k × (L / D) + ζ _in + ζ _out } × (Q ₁ / nD ² ) ²
[Q ₁ : When the required suction force X with respect to the paper 12 is the minimum value X ₁ (when the required static pressure P _s in the induction blower 37 is the minimum value P ₁ ), the air flowing in the communication member 35 Air volume (m ³ )]
When the paper 12 covers the suction openings of the suction holes 30 in a part of the suction hole group 32 on the second support base 27, the relational expression like Expression 16 is established.

[Formula 16]
n ≦ A-1
[A: Number of cover members 33 connected to the induction fan 37]
Substituting Equation 16 into Equation 15 yields Equation 17.

[Formula 17]
(100 × X) / (S × Y) ≦ 0.974 × {1 + k × (L / D) + ζ _in + ζ _out } × [Q ₁ / {(A−1) × D ² }] ²
In this way, the variables (L, D, S, Y, A, X, Q ₁ ) and their formulas k, ζ _in , ζ _out 17 represent the structure of the communication member 35 (that is, the diameter D ( m) and the length L (m) in the longitudinal direction (vertical direction). Here, the area S of the paper 12, the hole density Y of the communication holes 28 on the second conveying belt 23, and the number A of the cover members 33 connected to the induction blower 37 are the same as the arrangement configuration of the printer 11 of the present embodiment. It is determined in advance accordingly. The coefficients k, ζ _in , and ζ _out are estimated in advance according to the shapes of the inner wall, the inlet, and the outlet of the communication member 35. The minimum value X ₁ of the required attraction force X required for adsorbing the sheet 12 to the second conveyor belt 23 is determined by experiment.

Therefore, in the structural design of the communication member 35, the required air volume Q required for obtaining the required suction force X is obtained from the graph shown in FIG. Specifically, in the printer 11 of the present embodiment, the required static pressure P _s as required attraction force X as shown in Equation 13 is high is high, higher required static pressure P _s as shown in FIG. 6 Since the required air volume Q becomes lower, the maximum value Q ₁ of the required air volume Q corresponding to the minimum value X ₁ of the required suction force X is obtained. Then, the maximum value to Q ₁ the required air quantity Q determines the condition concerning the structure of the communicating member 35 by substituting the above equation 17, to design the communicating member 35 so as to satisfy the conditional expression. That is, the required static pressure P _s required for applying the required suction force X and the required air pressure Q corresponding to the required static pressure P _s defined by the static pressure-air volume curve of the induction blower 37 can be generated. The total pressure loss of air in the communication member 35 accompanying the drive of the induction blower 37 is set. Therefore, according to the printer 11 of the present embodiment, the required suction force X against the paper 12 even when the suction openings of the suction holes 30 in some of the suction hole groups 32 are open to the atmosphere. It is possible to act.

Next, the operation of the printer 11 configured as described above will be described.
When the sheet 12 conveyed from the first conveyance unit 15 to the second conveyance unit 17 is conveyed further downstream, the second drive pulley 19 is driven to drive the second drive pulley 19 while the induction blower 37 is driven. 2 The conveyance of the paper 12 by the conveyance belt 23 is started. When the sheet 12 is conveyed onto the second support 27 by the second conveying belt 23, the suction force of the induction blower 37 causes the negative pressure in the communication hole 38, the communication member 35, the communication hole 34, and the cover member 33. It acts on the paper 12 placed on the second conveyor belt 23 through the chamber 33a, the suction hole 30, and the communication hole 28.

  Here, as shown in FIG. 7A, the leading end of the paper 12 in the transport direction is on the suction hole group 32 arranged on the most upstream side among the plurality of suction hole groups 32 on the second support 27. When at least one suction hole row 31 among the plurality of suction hole rows 31 constituting the suction hole group 32 is in an open state to the atmosphere, the following occurs.

  That is, in the case shown in FIG. 7A, the negative pressure chamber 33a corresponding to the suction hole group 32 on the most upstream side is the downstream end (in FIG. 7) of the suction hole row 31 constituting the suction hole group 32. It is in an open state to the atmosphere via the suction hole row 31 at the right end). Therefore, even when the induction blower 37 is driven, a desired negative pressure cannot be obtained in the negative pressure chamber 33a because the induction blower 37 performs idle suction through the suction hole row 31, and the paper 12 On the other hand, the required suction force X necessary for adsorbing the paper 12 to the second transport belt 23 cannot be applied.

  On the other hand, the leading end in the transport direction of the paper 12 reaches the downstream end of the suction hole group 32 from the position shown in FIG. 7A (that is, the middle position of the suction hole group 32 on the most upstream side) ( In FIG. 7B, the sheet 12 closes all the suction holes 30 constituting the suction hole group 32. At this time, since the suction opening of the suction hole 30 in the suction hole group 32 on the downstream side of the suction hole group 32 is open to the atmosphere, the negative pressure chamber 33a on the downstream side among the negative pressure chambers 33a. Is in communication with the atmosphere. The negative pressure chamber 33a on the most upstream side communicates with the negative pressure chamber 33a on the downstream side through the communication member 35 and the inside of the induction blower 37. Therefore, even if the negative pressure chamber 33a on the upstream side exhausts the air in the negative pressure chamber 33a by driving the induction blower 37, the air always flows in through the negative pressure chamber 33a on the downstream side. There was a possibility that a desired negative pressure could not be obtained.

In this regard, in the present embodiment, when the induction blower 37 is driven in the state shown in FIG. 7B, the negative pressure chamber 33a corresponding to the suction hole group 32 via the suction hole group 32 on the downstream side. The total pressure loss of air in the communication member 35 is set so that the air does not flow more than a predetermined amount into the negative pressure chamber 33a on the upstream side through the communication member 35 and the induction fan 37 even if air flows into the air. Has been. That is, even if the suction opening of the suction hole 30 in the downstream suction hole group 32 is opened, the required suction force X is applied while considering the specifications (performance) in the induction blower 37. required static pressure P _s, and the required air volume Q as possible occurs corresponding to said predetermined Yosei圧P _s, the structure of the communicating member 35 is designed necessary.

  Therefore, with respect to the paper 12 that is transported while being placed on the second transport belt 23, before the leading end of the paper 12 in the transport direction reaches the downstream end of the most downstream suction hole group 32. Even in the stage, a desired negative pressure (suction pressure) can be generated in the negative pressure chamber 33a on the upstream side, and the suction force can be reliably applied.

According to the above embodiment, the following effects can be obtained.
(1) In the above embodiment, the negative pressure chamber corresponding to the downstream suction hole group 32 at the stage before the leading end in the transport direction of the paper 12 reaches the downstream end on the upper surface 27 a of the second support 27. Even when 33a is open to the atmosphere, the pressure loss of the air flowing into the communication member 35 connected to the downstream negative pressure chamber 33a due to the drive of the induction blower 37 is The shape of the communication member 35 is designed to have an appropriate value for generating a desired negative pressure in the upstream negative pressure chamber 33a corresponding to the suction hole group 32. For this reason, the plurality of negative pressure chambers 33a individually corresponding to the plurality of suction hole groups 32 are configured to be sucked by the common induction blower 37, thereby reducing the number of the induction blowers 37 and reducing the number of the induction blowers 37 installed. On the other hand, it is possible to reliably apply the suction force during the conveyance.

  (2) In the above embodiment, since the second conveying belt 23 that conveys the paper 12 on the upper surface 27a of the second support 27 is provided, the shape of the paper 12 is not limited to a long one. A sheet-like paper 12 can be applied. In addition, since the second transport belt 23 has a communication hole 28 that communicates with the suction hole 30 of the second support base 27, the suction force from the suction hole 30 reaches the paper 12 through the communication hole 28. As a result, the sheet 12 placed on the upper surface of the second conveyor belt 23 can be reliably adsorbed to the second conveyor belt 23.

  (3) In the above embodiment, the total pressure loss of air in the communication member 35 is the pressure loss in the shaft portion 35a of the communication member 35, the base end portion 35b connected to the cover member 33, and the tip portion 35c connected to the induction blower 37. It is set in consideration of. Therefore, it is possible to set the total pressure loss closer to the experimental value by counting the value reflecting the structure of the communication member 35 in detail.

  (4) In the above embodiment, the communication member 35 calculates the total pressure loss by summing up the pressure loss at the shaft portion 35 a, the base end portion 35 b connected to the cover member 33, and the tip end portion 35 c connected to the induction blower 37. At the same time, by considering the calculation result and the static pressure-air volume curve of the induction blower 37, a conditional expression relating to the structure of the communication member 35 necessary for applying a desired suction force to the paper 12 is calculated. Yes. Therefore, by designing the communication member 35 so as to satisfy this conditional expression, a desired suction force can be applied to the paper 12 more reliably.

  (5) In the above embodiment, even if the second transport belt 23 transports the paper 12 on the upper surface 27 a of the second support 27, the opening density of the communication holes 28 of the second transport belt 23. Is applied to Expression 17, the structure of the communication member 35 necessary for applying a desired suction force to the paper 12 can be determined.

In addition, you may change the said embodiment as follows.
In the above embodiment, when a long roll paper is applied as a target, the conveyor belts 22 and 23 may be omitted. At this time, the suction holes 30 on the support bases 26 and 27 that support the target are divided into a plurality of suction hole groups 32 in a direction perpendicular to the target transport direction, and the cover member 33 is individually provided for each suction hole group 32. It is desirable to arrange. According to this configuration, even when the roll paper is in a state where some of the suction holes 30 on the support bases 26 and 27 are in an open state, the suction hole groups 32 arranged at both ends in the width direction of the roll paper By designing the shape of the communication member 35 so that a desired negative pressure can be generated in the corresponding cover member 33, the suction force can be more reliably applied to the roll paper. In this case, the suction holes 30 on the support bases 26 and 27 function as openings for applying a suction force to the roll paper.

-In the said embodiment, when it is set as the structure which branches the communicating member 35 in the middle position, you may set the total pressure loss further including the pressure loss in the branch part.
In the above embodiment, when the communication member 35 is configured to have a throttle shape at an intermediate position, the total pressure loss may be set further including the pressure loss at the throttle portion.

In the above embodiment, when the communication member 35 is bent at an intermediate position, the total pressure loss may be set further including the pressure loss at the bent portion.
In the above embodiment, the recording apparatus is not limited to the ink jet printer 11. For example, the present invention can also be applied to printers of other printing styles such as a thermal transfer printer, a TA (Thermo Auto Chrome) printer, and a laser printer.

1 is a schematic diagram illustrating a printer according to an embodiment. The top view which shows the 2nd conveyance part of this embodiment. The schematic front view which shows the 2nd conveyance part of this embodiment. The partially broken schematic perspective view which shows the communicating member of this embodiment. The partially broken top view which shows the conveyance belt of this embodiment. The static pressure-air volume curve of the induction fan of this embodiment. (A) is a schematic plan view showing a state in which the sheet is partially closed in the suction hole group on the most upstream side, and (b) is a block diagram showing all the suction holes in the suction hole group on the most upstream side. The schematic plan view which shows the state immediately after.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... Inkjet printer as recording apparatus, 12 ... Paper as target, 22 ... 1st conveyance belt as a conveyance body, 23 ... 2nd conveyance belt as a conveyance body, 26 ... 1st support stand as a supporting member, 27: second support base as a support member, 27a: upper surface as a support surface, 28 ... communication hole as a communication portion, 30 ... suction hole, 32 ... suction hole group, 33a ... negative pressure chamber, 35 ... communication member, 35b ... proximal end of the connecting portion, the distal end portion of the 35c ... connecting portion, 37 ... attraction blower as a suction means, X ... required suction force, P s _... required static _{pressure, P total ...} total pressure loss, Q ... Required air volume.

Claims (3)

A support member having a support surface capable of supporting a target conveyed from the upstream side to the downstream side and having a plurality of suction holes formed on the support surface;
A plurality of negative pressure chambers individually communicating with each suction hole group when the suction holes are divided into a plurality of suction hole groups with respect to the plurality of suction holes of the support member;
A suction means capable of generating a negative pressure in each of the negative pressure chambers through communication members individually extending from the plurality of negative pressure chambers;
The communication member is formed to have a right cylindrical shape,
When the suction holes in the suction hole group communicating with some negative pressure chambers among the plurality of negative pressure chambers are closed, the target is adsorbed via the suction hole group communicating with the negative pressure chamber. In order to apply the required suction force required for the purpose, the required static pressure required to apply the required suction force and the required air volume corresponding to the required static pressure defined by the static pressure-air volume curve of the suction means So that the total pressure loss of the fluid in the communication member accompanying the driving of the suction means is set ,
The area of the target is S, the opening density of the openings for exerting a suction force on the target is Y, the length of the communication member is L, the diameter of the communication member is D, and the suction means is connected to the suction means. The number of negative pressure chambers is A, the coefficient of friction in the communication member is k, the pressure loss coefficient at the connection portion of the communication member to the negative pressure chamber is ζ _in , and the pressure loss coefficient at the connection portion of the communication member to the suction means is The conditional expression to be satisfied when ζ _out , the required suction force applied to the target is X, and the air volume corresponding to the minimum value X ₁ of the required suction force is Q ₁ is:
(100 × X) / (S × Y) ≦ 0.974 × {1 + k × (L / D) + ζ _in + ζ _out } × [Q ₁ / {(A−1) × D ² }] ²
Target adsorption device, characterized in that it. In the target adsorption | suction apparatus of Claim 1 ,
A transport body that moves to transport the target from the upstream side toward the downstream side while supporting the target;
The transport body has a plurality of communication portions capable of communicating with the suction holes in the support member during the movement of the transport body,
The support member can support the target over the transport body by the support surface,
The target suction apparatus according to claim 1, wherein the opening is the communication part of the transport body. A recording means for performing a recording process on the target;
Recording apparatus comprising the target adsorption apparatus according to claim 1 or claim 2.

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